// ******************************************************************
// Copyright � 2015-2018 nventive inc. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// ******************************************************************
#if !SILVERLIGHT
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Uno.Extensions
{
	public static class WeakReferenceExtensions
	{
		public static bool HasTarget<T>(this System.WeakReference<T> wr) where T : class
		{
			T value;
			return wr.TryGetTarget(out value);
		}

		public static T GetTarget<T>(this System.WeakReference<T> wr) where T : class
		{
			T value;
			if (!wr.TryGetTarget(out value))
			{
				value = default(T);
			}
			return value;
		}

		public static T FindOrCreate<T>(this System.WeakReference<T> wr, Func<T> factory) where T : class
		{
			T value;
			if (!wr.TryGetTarget(out value))
			{
				value = factory();
				wr.SetTarget(value);
			}
			return value;
		}
	}
}
#endif